Phase-angle indicator



July 6, l926. v

E. M. RUSSELL PHASE: ANGLE INDICATOR Fiid June v, 1922 4 Sheets-Sheet 1 July 6,1926. 1,591,186

E. M. RUSSELL PHASE ANGLE INDICATOR Y Filed June '7, 1922 4 Sheets-Sheet 2 Mawr@ Y .Y A

ATTORNEY July 6,1926. 1,591,186 i E. M. RUSSELL PHASE AANGLE INDICATOR u Filed June v,` 1922 4 sheets-sheet 5 m) m 11/ Q21 Y s )Q 3 |l',o|;| lll J1 ll I 17 Q Awb ll u I i 12. 21": EH 16 a* l 1 17 `Gf j 11.111. Wh, `:L 12

13 rg. e

July 6, 1926. 1,591,186

I' Y E. M. RUSSELL PHAS ANGLEv INDICATOR Filed June 7 1922 4 Sh'eetS-Sheet 4 tzy' V OAD Q zo` 15 l I Tg1/f @15.77 2s n 24 A W i I l/ENTOR ATTOREK Paieiited July 6, 1926.

more particularly to improved means forV EVERETT mnussnm., or*v SAGINAW7 MICHIGAN, AssIGNoR oF-TWo-'SIXTHS 'ro LEsLrE E. MACOMBER AND ONE-SIXTH ro'GEoRGE 1 3. wILLooxBorI-jror SAGINAW, MICHI- V GAN.

Appnca'tion inea :une 7,

This invention relates to devices formal;- mg electrical -measurements and pertains determiningthe charactery and measuring the amount of certainelectrical phenomena in circuits carrying alternatingcurrent.

2For example,l oneof the? applications of my improved instrumenty is the :measurement orfdetermination of thecorrectionifactor tol be used inascertaining the actual powerin a singlephase circuit. l' The actual powersupplied to an alternating current cir.

cuit in wattsis equal to the: effective volts multiplied by the eli'ective amperesftimes lthe fao cosine of therangle by which theyditfer in phase. y l.

My improveddevice is adapted to measure accuratelvthe,actual angleby which the volts and iamperesdifier in phase and from this determined angle its 'cosine may be aiscertained from-a trigonometric table, theV cosine then being employed in the formula: Actual'powerzEX-IX cosine A.

In.m v invention the correction factory.. cosine. A. is.` as above stated obtained by y v "the working relation of the split ring, 'the synchronous motor, the lineand the! amreading kangle A directly vfromthe instrument and 1 determining. the cosine yfromv a table. VIn 4this respect the Vmethod Adiffers -from that commonly employed for determin` watts. Vand then separately-to read the: watts' directly from the line by a wattmeter', then to divide the'wattmeterreading by the prod- Vuct of the readings of the ammeter and voltmeter,` the resultbeing a decimal correction factor, which by analysis actually represents the ycosine of the, angle of lag. or lead." It r1s apparent, however,;that when the difference in phase is slight, that is, when theangle of lag orleadis a small angle, a considerable difference in the angle may occur without Thereforep by reading the angle directly any. great difference in the cosine.

rimpulses all. posit1ve oral] negatlve.

PHASE-ANGLE INDICATOR.

1922. serial No. 566,673.2

much more directly and also more easily and quickly. l.. 'l

A further object'ofmy.inventionis to provide means for determining w1th considerable y accuracy the power correction factor for a three phase circuit. y y

T Withthefforegoing and'certain other ob-f jects infview which willappear later in the specilication, myinventioncomprisesrthe delents thereof. f i.

In lthe drawings'v Fig. 1 an instrumentarranged toindicate thea-ngle, the' cosine of which constitutes the true correction factor to be used in determining actual power. y

vices described and claimed andthe equiva-y Fig.2 is a'current curve of a single Yphase Fig. 3 is a diagram showing the method of connecting the ammete'r lto the single phase circuit. M '7 is -a frontvilewor1 ,Fig A; is a diagramr'naticl`view showing meter. y

, Fig. 5 is adiagrainmaticview .f.-:. h0 wi1 `v1;9:l the relative locationslof ,the 'split ringrr and its four brushes. l Y Fig. 6 isa side view of the mechams'm y grammatically.

F'g. 9 is a wiringdiagram of the instru,

. ment arranged for measuring the power correction v:tacto-r of single phase currents,

Fig 10 is a diagrammatic representation of a three phase current,A with impulsesjhalf negative and half positive. y

Fig. y11 isa similar representation with Fig. l2 is a diagigraniY showing the connec- 80 contained in the instrument illustrated in g Flg. 1,'show1ng the wlrlng connections dla- 1 tions for deterininingpower factor( in a three phase circuit and showing one position of the split ring.

Figs. 13 and 14 show successive positions 0f the. Split ring... Figs. 15,16, 17 are diagrams' showing the ammeter connections corresponding to the vpositions of the split ring shown in Figs.

' Aslis'clearlyshownin the drawings`,'tlie instrument consists preferably in a ease 1 of any suitable kind, carrying a graduated dial 2 and a pointer 3 and also carrying'an in dicating ammeter 4 or any equivalent polarity indicator and provided with suitable lline connections veend G and volt-meter connections? and 8. l y v n, Y. I

`Referring to Fig. 2`, which represents a typical current diagram,` showing two cycles of operation of a'single phase current,jit will be seeirfromrthedimensions below the y base-line.representing electrical 'degrees that CII the first threehundred and sixtyk degrees is equally divided into a positiveimpulse and a negative impulse. From the dimensions fa-fboveV the basefline, 4 whichv represent degreesof motor rotation in all-our poleimotor., it s will kbe see-n Vthat the lirst one hundred y'eighty degrees of actual revolution o'l' the 1 motor results mi va positive and a negative It the tiveY and ,thegother half negative, thei'esu'lt! sant reading onl a polarity ammeter, suoli asmA iii-Fig. 3, will be Zero. Ifwithout moving the brushes there occurs lag orlead iiifthe Y current Vwith respect. Vto the voltage, Y ythen the resultant reading ot the ammeter willnot be zero andthe indicator 4 ot the a-n-iineter will show a positive ora negative reading. p Y y Vlt isfairiinp'oitant object ot my invention toprovide means .ifhereby current iinp-ulses, such as those indicated by the heavy line in Fig. 2, canA be taken at'will 'from the lineuand transmitted to the indicating. ainmeter 4, in order that the ,amineter may indicatethe presence of lag or lead. A To this end,1 provide as ajmeans Vfor taking the impulses from the line, a split ring 9 Fig. 12, and' preferably four brushes, of which one pair, 10 and 11, connects to the indicatingy ammeter`f4 through a Y current transformer 24 when theV split ring is in the positionshown in Fig. 12., andr another pair 12 and is in lik'efmanner adapted to. be connected to the line through a'transtormer 25. To take ott the proper current im pulses, it is necessary that split ring 9 be revolved in yexact synchronism with the current in the line. Y

As one means for revolving the ring 9 in perfect synchronisin with the'E. M. F.,in the'line, the ring 9 may lbe rotated by` means of a synchronous single phase motor 15,

which takes the current'from the line. Any other su'itablemeans may 'be e'inpll'o'yedffor revolving the ring 9 insynchronisni with the line, but I have found in practice that the synchronous single phase motor 15 answers the' purpose satisfactorily.

Referring now to Fig. 4, it will be seen lthaty it during the time the split ring VisV revolving Vin synchronisin Y with ythe liiie and assuming that the ammeter `A reads zero in consequence 'of havingthe brushes 10 and 11 so set asto take that partoftheimpulses represented the heavy part'ot the curve in I Fig. 2, it iscvident thatsliifting the brushes 10 and 11 by movement .ot rotationto the right or to thel lett rwill result in correspondvingly changing the nature of the impulses which are transmitted tothe ammetei" 4.

that is, instead of'l each impulse being halt `positive'and half negative, as shownby `the ulnequally divided positive and negative and the resultant will' be'shown as a positive or negative reading ofV the'ammeter 4. f

Suppose the yimpulses to be equally divided positive and negative, Vand theammeter reading to be zero, this conditionlwill correspond to no lag and no' lead of the current' with Vrespect to the voltage.

y, Now, assume that the current departsY in phase 4Iroin that 'of the voltage by an amount Ajheav'y line in Fig. 2, each impulse'V may be l corresponding vto 'a' certain angle ofv lag' or lead` then the resultant'impulse'will be' indicated on the tivegreading.l .v Y To bring the 1readingjoi" the ammetei'back to zero, the brushes 10, 11,12, 13' are simulammete'r Vas a v'positive or' 'negataneous'ly rotated through an angle loi" adjustment, the amount of which angle'depeuds uponwthe amount of lag or' lead present in the line circuit.

To ad'ust the 'ourlbiushesthrough such angles'-ottrevolution,l mountfthein on any suitable ievolvableicrame or spideig: as for rexample that illustrated in Figs. 6,7,15

where 16 is a rotatable' brush holder,which may be in th'eform of aring' upon which the brushes aremounted in the usual inann'er. The brush holder V16'may be carried by ayoke 17, the yoke secured to a spindle'lfl carrying a' gear 19 meshing'with apinion 20, the pinionv carrying a knob 21'and-a..

pointerl 3. Thusby turning the knob '21 and pointer 3 the brush holder'16I may be turned through any desired angle of adjustment, andthe amount of that angle willfbe shown 'by 'the 'movement 'of the pointer' 3 which may travel aroundv a' graduated scale 22 Y negative reading to zero, the pointer 3 will 19, the pointer 3 may be`made'to read'dihave swung through an arcwliich can be measured by the graduations of scale 22 and by; suitably arranging the scale of these graduatlons and the ratio ofgea1's20 and rectly in terins of electrical degrees, as shown by the dimensions below Athe baseline in It is evidentitliat-'any part of .the grad-l uated scale 22 may be read as readily asany othervpart and that the `angle of movement of .Y

`.pointer 3 Vnecessaryto produce` Zero reading j Tzo Reading the angle through which the pointerhas been moved, and referring to 'a of the ammeter 4 isl the actua-l` angle A ,in the formula: Actual power=E I cos1ne cosine table reveals a decimal ,which is'the correct `factor cosine A in the, formula, and multiplying this decimal by the product of Athe voltage times the amperes gives the actual power.l The decimal itselfl is` known as the .power factor.

To readthe voltage and the lcurrent required for the' computation of the above formula, it is necessary to vinstall a volt-4 meter and ammeter in the line'in thel usual manner.v j' y f" f My present invention relates tothe determination of the power jfactor which inthe formula is, as above stated, cosine A;

YIn thev foregoing description it has Vbeen assume'd'that the zero position of the volta`ge',.th at is, theposition where the voltage curve crosses the'b'a'selline, was in register with the position of the current impulse in order to produce a zero reading of the po#l larity ammeter 4.

In practice, however, it is necessary to actuallylocate electrically the position of the' zero point of voltage with respect to the .zero point of current when the two are in register. To locate the zero point of the voltage for purposes of calibration, I tem- Vporarily employ la polarity volt-meter 23, connecting it as shown by dotted `lines in Fig. 9 and using a volt-meter4 resistance R. A double throw switch, S, is usedto connect the brushes, with either the ammeter, or the volt-meteras desired. I adjust the position of thev brushes by means4 of knob 21 so that the *volt-meter 23 willread Zero and then adjust the'pointer 3 so that it, will read zero on vthe graduated scale 22. Y The foregoing description relates to the instrument as adapted for the 'determining of power factor in single4` phase circuits.

The same `instrument may be employed for determination .of power factor in polyphase circuits such as three phase, andreference may know bel had to the drawings, Figs 10 and 11,1in which Fig. lO'represents diagrammati cally a three-phase current, the 'Y heavy portions of the curve representing the three Vsuccessive,impulses corresponding to lamotor rotation of threehundred sixty electricfal degrees. -V Y n I In'Fig. 10 the iljnpulses picked up by the brushes onl thesplit ringare half-'positive 'n and half negative, las indicated by the 'heavy lines, and`con`s'equently the reading of am-y metery 4 for that condition vwill bezero..

In' Fig. l11 the impulses'beingpicke'd up` lare either all, positive or all Ynegative,dey pending upon the adjustment of the brushes with-irela'tionto the split ring. `The same principle of operation applies-in the meas-- urement of'three phasefcircuitsas-was eml ployed in theV lmeasurem'ent `of singlephase circuits. `However,t he relativel positions ofil :the brushesfor single phase Vcircuit observa- Y i tions are as vindicated in'Fig. 4, and for `three'phase circuits as indicated yin Fig. 12."

' Referring toFigI 12, which vis a diagrammatic representation" of one'yway `of. makin gV the connections for determining the power factor of. a vthree phase circuit, 24 and 25 are current transformers applied 'in two of the three line wiresjand connected respectively to, the brushes*v 10,11, and .12, 13.

Two of the line wires are connected yto single phase synchronous motor 15; I Figs.- 12, 18,-14-showthe vrespective positions ofsplit ring 9` with relation to the brushes, at which' positions the three current impulses which are indicated by heavy `lines in Fig. 10 are taken ofl'rbyfthe brushes.

Figs. 15, 16 and .17 are 'diagrammatic repy" gresentations lrespectively of the electricallv 'connections 'to the ammeter4 at theytimeswhen the split ring 9 is inthe positions shown in Figs. 12, 13 and 14.

In Fig. 12, the split ring 9 Vis in such position that ammeter A is in circuit with current transformer 24 connected to brushes 11 and -13 and current transformer 25'isV shorted through brushes 10l and 12.

Fig. 13 ammeter A is in circuit with trans'- former 25 through brushes 12 and V13 and current transformer No. y24 is shorted through brushes 10 and 11.

llO

In'the position of split ring 9 shown inf In the ring position shown in .'Fig. 14

brushes 11, 12'and'13 are shorted and brush 1() isconnected in common to transformers 24 and 25. This connection is necessary on 'an unbalanced three phase load, where the ring 9 isjrotated instep with .the E. M.`F.,

the ring being vdriven by a synchronous single phase motor'15 or any equivalent of it. In'operation the method is vthe same as f when measuring power factor of a single phase circuit, that is to say,zwith the pointer 3 adjusted to read zero when vthe-current is without lag or lead, itwill read either positive or negative when lag or lead is present, 'and `by turning the knob 21 and pointer?)V and thereby adjusting the positions of the,V

-tour brushes on the split lring so as to restorenthe ainmeter to its original` zero .reading angl noting the angular difference between the two positions of the pointer 3.

there may'V be read ofiE from the graduated scale 22 an angle which, referredtothe cosine table, produces the required power factor in the 'form of a decimal.' Y

Having thus described my invention, what I claim and desire to secure by Letters Patlent isi Y l'. In a device `for in'dica'tinf he amount 'ofV current or lead in a circuit,- 'an impulse-transmitting member. revolvableV in 'i synchronism with the ii'npulsesV of Athe M. YF. to Vbe measured,V ay plurality of brushes contacting withsaid memberv and rotatablewith respect thereto,` a polarity iny dicator in series between certainV oi said brushes, other of saidbrushes in series with the circuit, and indicating means operatively :connected tosaid brushes 'and adaptedto.

indicate angularly adjusted positions of said 2. In a device for indicating lag or lead in a circuit, a split ring revolvable ijn synclironisin with the M. F. to bemeasured, a revolvable brush holder,a plurality of brushes carriedby said holder, an ammeter connected'in series between certainv oi'said brushes, other of said brushes connected in series with `the circuit, indicating means operatively connected` to said revolvable brushy holderand adapted to indicate angularly adjustedpositionsA of said brushes. v3. In a. device for indicating the amouii Vof'eurrent lag or lead in a circuit,- a split 4. In a devicefor ,indicating lag orlead in an alternating current circuit, a split ring, an alternating current synchronous motor Vadapted to revolve said ring in syncliroism vwith the impulses of said E., M. F., a re-.,

volvable brush holder, brushes on said holder. contacting with said ring, airammeter connected inV series betweenA two of sait brushes, other two brushes connected in sei'ies with themain. circuit, Aand indicating,

means adapted to indicate angulargdifferences between successive angularlyradjusted positions of saidy brush holder.

'5.V In a device lor indicatingltheamount otcurrent lag or lead in a circuit, an im,

pulse-transinitting member i revolvable `in synehronisin with the impulse of f the E. M. F. to be measured, a pluralityo brushes contacting with-said member, said member and brushes capableof relative-cir cuniferential adJuStment, a Vpolarity 1ndi` reator inv series A between certain of fsaid brushes, other of said brushes in series with the circuit, and indicating means operatively connected'to said brushes, and adapted to indicate the relative angularly adjusted 'positions ofsaid brushes with respect to said inemben i. f In testimony whereof Ia-iix'my signa-ture.

EVERETT M. RUSSELL. 

